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-rw-r--r--pkg/sentry/fsimpl/proc/BUILD49
-rw-r--r--pkg/sentry/fsimpl/proc/filesystems.go25
-rw-r--r--pkg/sentry/fsimpl/proc/loadavg.go40
-rw-r--r--pkg/sentry/fsimpl/proc/meminfo.go77
-rw-r--r--pkg/sentry/fsimpl/proc/mounts.go33
-rw-r--r--pkg/sentry/fsimpl/proc/net.go338
-rw-r--r--pkg/sentry/fsimpl/proc/net_test.go78
-rw-r--r--pkg/sentry/fsimpl/proc/proc.go16
-rw-r--r--pkg/sentry/fsimpl/proc/stat.go127
-rw-r--r--pkg/sentry/fsimpl/proc/sys.go51
-rw-r--r--pkg/sentry/fsimpl/proc/task.go261
-rw-r--r--pkg/sentry/fsimpl/proc/version.go68
12 files changed, 1163 insertions, 0 deletions
diff --git a/pkg/sentry/fsimpl/proc/BUILD b/pkg/sentry/fsimpl/proc/BUILD
new file mode 100644
index 000000000..3d8a4deaf
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/BUILD
@@ -0,0 +1,49 @@
+load("//tools/go_stateify:defs.bzl", "go_library", "go_test")
+
+package(licenses = ["notice"])
+
+go_library(
+ name = "proc",
+ srcs = [
+ "filesystems.go",
+ "loadavg.go",
+ "meminfo.go",
+ "mounts.go",
+ "net.go",
+ "proc.go",
+ "stat.go",
+ "sys.go",
+ "task.go",
+ "version.go",
+ ],
+ importpath = "gvisor.dev/gvisor/pkg/sentry/fsimpl/proc",
+ deps = [
+ "//pkg/abi/linux",
+ "//pkg/binary",
+ "//pkg/log",
+ "//pkg/sentry/context",
+ "//pkg/sentry/fs",
+ "//pkg/sentry/inet",
+ "//pkg/sentry/kernel",
+ "//pkg/sentry/limits",
+ "//pkg/sentry/mm",
+ "//pkg/sentry/socket",
+ "//pkg/sentry/socket/unix",
+ "//pkg/sentry/socket/unix/transport",
+ "//pkg/sentry/usage",
+ "//pkg/sentry/usermem",
+ "//pkg/sentry/vfs",
+ ],
+)
+
+go_test(
+ name = "proc_test",
+ size = "small",
+ srcs = ["net_test.go"],
+ embed = [":proc"],
+ deps = [
+ "//pkg/abi/linux",
+ "//pkg/sentry/context/contexttest",
+ "//pkg/sentry/inet",
+ ],
+)
diff --git a/pkg/sentry/fsimpl/proc/filesystems.go b/pkg/sentry/fsimpl/proc/filesystems.go
new file mode 100644
index 000000000..c36c4aff5
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/filesystems.go
@@ -0,0 +1,25 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+// filesystemsData implements vfs.DynamicBytesSource for /proc/filesystems.
+//
+// +stateify savable
+type filesystemsData struct{}
+
+// TODO(b/138862512): Implement vfs.DynamicBytesSource.Generate for
+// filesystemsData. We would need to retrive filesystem names from
+// vfs.VirtualFilesystem. Also needs vfs replacement for
+// fs.Filesystem.AllowUserList() and fs.FilesystemRequiresDev.
diff --git a/pkg/sentry/fsimpl/proc/loadavg.go b/pkg/sentry/fsimpl/proc/loadavg.go
new file mode 100644
index 000000000..9135afef1
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/loadavg.go
@@ -0,0 +1,40 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+import (
+ "bytes"
+ "fmt"
+
+ "gvisor.dev/gvisor/pkg/sentry/context"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+)
+
+// loadavgData backs /proc/loadavg.
+//
+// +stateify savable
+type loadavgData struct{}
+
+var _ vfs.DynamicBytesSource = (*loadavgData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (d *loadavgData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ // TODO(b/62345059): Include real data in fields.
+ // Column 1-3: CPU and IO utilization of the last 1, 5, and 10 minute periods.
+ // Column 4-5: currently running processes and the total number of processes.
+ // Column 6: the last process ID used.
+ fmt.Fprintf(buf, "%.2f %.2f %.2f %d/%d %d\n", 0.00, 0.00, 0.00, 0, 0, 0)
+ return nil
+}
diff --git a/pkg/sentry/fsimpl/proc/meminfo.go b/pkg/sentry/fsimpl/proc/meminfo.go
new file mode 100644
index 000000000..9a827cd66
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/meminfo.go
@@ -0,0 +1,77 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+import (
+ "bytes"
+ "fmt"
+
+ "gvisor.dev/gvisor/pkg/sentry/context"
+ "gvisor.dev/gvisor/pkg/sentry/kernel"
+ "gvisor.dev/gvisor/pkg/sentry/usage"
+ "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+)
+
+// meminfoData implements vfs.DynamicBytesSource for /proc/meminfo.
+//
+// +stateify savable
+type meminfoData struct {
+ // k is the owning Kernel.
+ k *kernel.Kernel
+}
+
+var _ vfs.DynamicBytesSource = (*meminfoData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (d *meminfoData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ mf := d.k.MemoryFile()
+ mf.UpdateUsage()
+ snapshot, totalUsage := usage.MemoryAccounting.Copy()
+ totalSize := usage.TotalMemory(mf.TotalSize(), totalUsage)
+ anon := snapshot.Anonymous + snapshot.Tmpfs
+ file := snapshot.PageCache + snapshot.Mapped
+ // We don't actually have active/inactive LRUs, so just make up numbers.
+ activeFile := (file / 2) &^ (usermem.PageSize - 1)
+ inactiveFile := file - activeFile
+
+ fmt.Fprintf(buf, "MemTotal: %8d kB\n", totalSize/1024)
+ memFree := (totalSize - totalUsage) / 1024
+ // We use MemFree as MemAvailable because we don't swap.
+ // TODO(rahat): When reclaim is implemented the value of MemAvailable
+ // should change.
+ fmt.Fprintf(buf, "MemFree: %8d kB\n", memFree)
+ fmt.Fprintf(buf, "MemAvailable: %8d kB\n", memFree)
+ fmt.Fprintf(buf, "Buffers: 0 kB\n") // memory usage by block devices
+ fmt.Fprintf(buf, "Cached: %8d kB\n", (file+snapshot.Tmpfs)/1024)
+ // Emulate a system with no swap, which disables inactivation of anon pages.
+ fmt.Fprintf(buf, "SwapCache: 0 kB\n")
+ fmt.Fprintf(buf, "Active: %8d kB\n", (anon+activeFile)/1024)
+ fmt.Fprintf(buf, "Inactive: %8d kB\n", inactiveFile/1024)
+ fmt.Fprintf(buf, "Active(anon): %8d kB\n", anon/1024)
+ fmt.Fprintf(buf, "Inactive(anon): 0 kB\n")
+ fmt.Fprintf(buf, "Active(file): %8d kB\n", activeFile/1024)
+ fmt.Fprintf(buf, "Inactive(file): %8d kB\n", inactiveFile/1024)
+ fmt.Fprintf(buf, "Unevictable: 0 kB\n") // TODO(b/31823263)
+ fmt.Fprintf(buf, "Mlocked: 0 kB\n") // TODO(b/31823263)
+ fmt.Fprintf(buf, "SwapTotal: 0 kB\n")
+ fmt.Fprintf(buf, "SwapFree: 0 kB\n")
+ fmt.Fprintf(buf, "Dirty: 0 kB\n")
+ fmt.Fprintf(buf, "Writeback: 0 kB\n")
+ fmt.Fprintf(buf, "AnonPages: %8d kB\n", anon/1024)
+ fmt.Fprintf(buf, "Mapped: %8d kB\n", file/1024) // doesn't count mapped tmpfs, which we don't know
+ fmt.Fprintf(buf, "Shmem: %8d kB\n", snapshot.Tmpfs/1024)
+ return nil
+}
diff --git a/pkg/sentry/fsimpl/proc/mounts.go b/pkg/sentry/fsimpl/proc/mounts.go
new file mode 100644
index 000000000..e81b1e910
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/mounts.go
@@ -0,0 +1,33 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+import "gvisor.dev/gvisor/pkg/sentry/kernel"
+
+// TODO(b/138862512): Implement mountInfoFile and mountsFile.
+
+// mountInfoFile implements vfs.DynamicBytesSource for /proc/[pid]/mountinfo.
+//
+// +stateify savable
+type mountInfoFile struct {
+ t *kernel.Task
+}
+
+// mountsFile implements vfs.DynamicBytesSource for /proc/[pid]/mounts.
+//
+// +stateify savable
+type mountsFile struct {
+ t *kernel.Task
+}
diff --git a/pkg/sentry/fsimpl/proc/net.go b/pkg/sentry/fsimpl/proc/net.go
new file mode 100644
index 000000000..fd46eebf8
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/net.go
@@ -0,0 +1,338 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+import (
+ "bytes"
+ "fmt"
+
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/binary"
+ "gvisor.dev/gvisor/pkg/log"
+ "gvisor.dev/gvisor/pkg/sentry/context"
+ "gvisor.dev/gvisor/pkg/sentry/fs"
+ "gvisor.dev/gvisor/pkg/sentry/inet"
+ "gvisor.dev/gvisor/pkg/sentry/kernel"
+ "gvisor.dev/gvisor/pkg/sentry/socket"
+ "gvisor.dev/gvisor/pkg/sentry/socket/unix"
+ "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+)
+
+// ifinet6 implements vfs.DynamicBytesSource for /proc/net/if_inet6.
+//
+// +stateify savable
+type ifinet6 struct {
+ s inet.Stack
+}
+
+var _ vfs.DynamicBytesSource = (*ifinet6)(nil)
+
+func (n *ifinet6) contents() []string {
+ var lines []string
+ nics := n.s.Interfaces()
+ for id, naddrs := range n.s.InterfaceAddrs() {
+ nic, ok := nics[id]
+ if !ok {
+ // NIC was added after NICNames was called. We'll just
+ // ignore it.
+ continue
+ }
+
+ for _, a := range naddrs {
+ // IPv6 only.
+ if a.Family != linux.AF_INET6 {
+ continue
+ }
+
+ // Fields:
+ // IPv6 address displayed in 32 hexadecimal chars without colons
+ // Netlink device number (interface index) in hexadecimal (use nic id)
+ // Prefix length in hexadecimal
+ // Scope value (use 0)
+ // Interface flags
+ // Device name
+ lines = append(lines, fmt.Sprintf("%032x %02x %02x %02x %02x %8s\n", a.Addr, id, a.PrefixLen, 0, a.Flags, nic.Name))
+ }
+ }
+ return lines
+}
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (n *ifinet6) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ for _, l := range n.contents() {
+ buf.WriteString(l)
+ }
+ return nil
+}
+
+// netDev implements vfs.DynamicBytesSource for /proc/net/dev.
+//
+// +stateify savable
+type netDev struct {
+ s inet.Stack
+}
+
+var _ vfs.DynamicBytesSource = (*netDev)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (n *netDev) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ interfaces := n.s.Interfaces()
+ buf.WriteString("Inter-| Receive | Transmit\n")
+ buf.WriteString(" face |bytes packets errs drop fifo frame compressed multicast|bytes packets errs drop fifo colls carrier compressed\n")
+
+ for _, i := range interfaces {
+ // Implements the same format as
+ // net/core/net-procfs.c:dev_seq_printf_stats.
+ var stats inet.StatDev
+ if err := n.s.Statistics(&stats, i.Name); err != nil {
+ log.Warningf("Failed to retrieve interface statistics for %v: %v", i.Name, err)
+ continue
+ }
+ fmt.Fprintf(
+ buf,
+ "%6s: %7d %7d %4d %4d %4d %5d %10d %9d %8d %7d %4d %4d %4d %5d %7d %10d\n",
+ i.Name,
+ // Received
+ stats[0], // bytes
+ stats[1], // packets
+ stats[2], // errors
+ stats[3], // dropped
+ stats[4], // fifo
+ stats[5], // frame
+ stats[6], // compressed
+ stats[7], // multicast
+ // Transmitted
+ stats[8], // bytes
+ stats[9], // packets
+ stats[10], // errors
+ stats[11], // dropped
+ stats[12], // fifo
+ stats[13], // frame
+ stats[14], // compressed
+ stats[15], // multicast
+ )
+ }
+
+ return nil
+}
+
+// netUnix implements vfs.DynamicBytesSource for /proc/net/unix.
+//
+// +stateify savable
+type netUnix struct {
+ k *kernel.Kernel
+}
+
+var _ vfs.DynamicBytesSource = (*netUnix)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (n *netUnix) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ buf.WriteString("Num RefCount Protocol Flags Type St Inode Path\n")
+ for _, se := range n.k.ListSockets() {
+ s := se.Sock.Get()
+ if s == nil {
+ log.Debugf("Couldn't resolve weakref %v in socket table, racing with destruction?", se.Sock)
+ continue
+ }
+ sfile := s.(*fs.File)
+ if family, _, _ := sfile.FileOperations.(socket.Socket).Type(); family != linux.AF_UNIX {
+ s.DecRef()
+ // Not a unix socket.
+ continue
+ }
+ sops := sfile.FileOperations.(*unix.SocketOperations)
+
+ addr, err := sops.Endpoint().GetLocalAddress()
+ if err != nil {
+ log.Warningf("Failed to retrieve socket name from %+v: %v", sfile, err)
+ addr.Addr = "<unknown>"
+ }
+
+ sockFlags := 0
+ if ce, ok := sops.Endpoint().(transport.ConnectingEndpoint); ok {
+ if ce.Listening() {
+ // For unix domain sockets, linux reports a single flag
+ // value if the socket is listening, of __SO_ACCEPTCON.
+ sockFlags = linux.SO_ACCEPTCON
+ }
+ }
+
+ // In the socket entry below, the value for the 'Num' field requires
+ // some consideration. Linux prints the address to the struct
+ // unix_sock representing a socket in the kernel, but may redact the
+ // value for unprivileged users depending on the kptr_restrict
+ // sysctl.
+ //
+ // One use for this field is to allow a privileged user to
+ // introspect into the kernel memory to determine information about
+ // a socket not available through procfs, such as the socket's peer.
+ //
+ // In gvisor, returning a pointer to our internal structures would
+ // be pointless, as it wouldn't match the memory layout for struct
+ // unix_sock, making introspection difficult. We could populate a
+ // struct unix_sock with the appropriate data, but even that
+ // requires consideration for which kernel version to emulate, as
+ // the definition of this struct changes over time.
+ //
+ // For now, we always redact this pointer.
+ fmt.Fprintf(buf, "%#016p: %08X %08X %08X %04X %02X %5d",
+ (*unix.SocketOperations)(nil), // Num, pointer to kernel socket struct.
+ sfile.ReadRefs()-1, // RefCount, don't count our own ref.
+ 0, // Protocol, always 0 for UDS.
+ sockFlags, // Flags.
+ sops.Endpoint().Type(), // Type.
+ sops.State(), // State.
+ sfile.InodeID(), // Inode.
+ )
+
+ // Path
+ if len(addr.Addr) != 0 {
+ if addr.Addr[0] == 0 {
+ // Abstract path.
+ fmt.Fprintf(buf, " @%s", string(addr.Addr[1:]))
+ } else {
+ fmt.Fprintf(buf, " %s", string(addr.Addr))
+ }
+ }
+ fmt.Fprintf(buf, "\n")
+
+ s.DecRef()
+ }
+ return nil
+}
+
+// netTCP implements vfs.DynamicBytesSource for /proc/net/tcp.
+//
+// +stateify savable
+type netTCP struct {
+ k *kernel.Kernel
+}
+
+var _ vfs.DynamicBytesSource = (*netTCP)(nil)
+
+func (n *netTCP) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ t := kernel.TaskFromContext(ctx)
+ buf.WriteString(" sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode \n")
+ for _, se := range n.k.ListSockets() {
+ s := se.Sock.Get()
+ if s == nil {
+ log.Debugf("Couldn't resolve weakref %+v in socket table, racing with destruction?", se.Sock)
+ continue
+ }
+ sfile := s.(*fs.File)
+ sops, ok := sfile.FileOperations.(socket.Socket)
+ if !ok {
+ panic(fmt.Sprintf("Found non-socket file in socket table: %+v", sfile))
+ }
+ if family, stype, _ := sops.Type(); !(family == linux.AF_INET && stype == linux.SOCK_STREAM) {
+ s.DecRef()
+ // Not tcp4 sockets.
+ continue
+ }
+
+ // Linux's documentation for the fields below can be found at
+ // https://www.kernel.org/doc/Documentation/networking/proc_net_tcp.txt.
+ // For Linux's implementation, see net/ipv4/tcp_ipv4.c:get_tcp4_sock().
+ // Note that the header doesn't contain labels for all the fields.
+
+ // Field: sl; entry number.
+ fmt.Fprintf(buf, "%4d: ", se.ID)
+
+ portBuf := make([]byte, 2)
+
+ // Field: local_adddress.
+ var localAddr linux.SockAddrInet
+ if local, _, err := sops.GetSockName(t); err == nil {
+ localAddr = *local.(*linux.SockAddrInet)
+ }
+ binary.LittleEndian.PutUint16(portBuf, localAddr.Port)
+ fmt.Fprintf(buf, "%08X:%04X ",
+ binary.LittleEndian.Uint32(localAddr.Addr[:]),
+ portBuf)
+
+ // Field: rem_address.
+ var remoteAddr linux.SockAddrInet
+ if remote, _, err := sops.GetPeerName(t); err == nil {
+ remoteAddr = *remote.(*linux.SockAddrInet)
+ }
+ binary.LittleEndian.PutUint16(portBuf, remoteAddr.Port)
+ fmt.Fprintf(buf, "%08X:%04X ",
+ binary.LittleEndian.Uint32(remoteAddr.Addr[:]),
+ portBuf)
+
+ // Field: state; socket state.
+ fmt.Fprintf(buf, "%02X ", sops.State())
+
+ // Field: tx_queue, rx_queue; number of packets in the transmit and
+ // receive queue. Unimplemented.
+ fmt.Fprintf(buf, "%08X:%08X ", 0, 0)
+
+ // Field: tr, tm->when; timer active state and number of jiffies
+ // until timer expires. Unimplemented.
+ fmt.Fprintf(buf, "%02X:%08X ", 0, 0)
+
+ // Field: retrnsmt; number of unrecovered RTO timeouts.
+ // Unimplemented.
+ fmt.Fprintf(buf, "%08X ", 0)
+
+ // Field: uid.
+ uattr, err := sfile.Dirent.Inode.UnstableAttr(ctx)
+ if err != nil {
+ log.Warningf("Failed to retrieve unstable attr for socket file: %v", err)
+ fmt.Fprintf(buf, "%5d ", 0)
+ } else {
+ fmt.Fprintf(buf, "%5d ", uint32(uattr.Owner.UID.In(t.UserNamespace()).OrOverflow()))
+ }
+
+ // Field: timeout; number of unanswered 0-window probes.
+ // Unimplemented.
+ fmt.Fprintf(buf, "%8d ", 0)
+
+ // Field: inode.
+ fmt.Fprintf(buf, "%8d ", sfile.InodeID())
+
+ // Field: refcount. Don't count the ref we obtain while deferencing
+ // the weakref to this socket.
+ fmt.Fprintf(buf, "%d ", sfile.ReadRefs()-1)
+
+ // Field: Socket struct address. Redacted due to the same reason as
+ // the 'Num' field in /proc/net/unix, see netUnix.ReadSeqFileData.
+ fmt.Fprintf(buf, "%#016p ", (*socket.Socket)(nil))
+
+ // Field: retransmit timeout. Unimplemented.
+ fmt.Fprintf(buf, "%d ", 0)
+
+ // Field: predicted tick of soft clock (delayed ACK control data).
+ // Unimplemented.
+ fmt.Fprintf(buf, "%d ", 0)
+
+ // Field: (ack.quick<<1)|ack.pingpong, Unimplemented.
+ fmt.Fprintf(buf, "%d ", 0)
+
+ // Field: sending congestion window, Unimplemented.
+ fmt.Fprintf(buf, "%d ", 0)
+
+ // Field: Slow start size threshold, -1 if threshold >= 0xFFFF.
+ // Unimplemented, report as large threshold.
+ fmt.Fprintf(buf, "%d", -1)
+
+ fmt.Fprintf(buf, "\n")
+
+ s.DecRef()
+ }
+
+ return nil
+}
diff --git a/pkg/sentry/fsimpl/proc/net_test.go b/pkg/sentry/fsimpl/proc/net_test.go
new file mode 100644
index 000000000..20a77a8ca
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/net_test.go
@@ -0,0 +1,78 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+import (
+ "bytes"
+ "reflect"
+ "testing"
+
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/sentry/context/contexttest"
+ "gvisor.dev/gvisor/pkg/sentry/inet"
+)
+
+func newIPv6TestStack() *inet.TestStack {
+ s := inet.NewTestStack()
+ s.SupportsIPv6Flag = true
+ return s
+}
+
+func TestIfinet6NoAddresses(t *testing.T) {
+ n := &ifinet6{s: newIPv6TestStack()}
+ var buf bytes.Buffer
+ n.Generate(contexttest.Context(t), &buf)
+ if buf.Len() > 0 {
+ t.Errorf("n.Generate() generated = %v, want = %v", buf.Bytes(), []byte{})
+ }
+}
+
+func TestIfinet6(t *testing.T) {
+ s := newIPv6TestStack()
+ s.InterfacesMap[1] = inet.Interface{Name: "eth0"}
+ s.InterfaceAddrsMap[1] = []inet.InterfaceAddr{
+ {
+ Family: linux.AF_INET6,
+ PrefixLen: 128,
+ Addr: []byte("\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f"),
+ },
+ }
+ s.InterfacesMap[2] = inet.Interface{Name: "eth1"}
+ s.InterfaceAddrsMap[2] = []inet.InterfaceAddr{
+ {
+ Family: linux.AF_INET6,
+ PrefixLen: 128,
+ Addr: []byte("\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f"),
+ },
+ }
+ want := map[string]struct{}{
+ "000102030405060708090a0b0c0d0e0f 01 80 00 00 eth0\n": {},
+ "101112131415161718191a1b1c1d1e1f 02 80 00 00 eth1\n": {},
+ }
+
+ n := &ifinet6{s: s}
+ contents := n.contents()
+ if len(contents) != len(want) {
+ t.Errorf("Got len(n.contents()) = %d, want = %d", len(contents), len(want))
+ }
+ got := map[string]struct{}{}
+ for _, l := range contents {
+ got[l] = struct{}{}
+ }
+
+ if !reflect.DeepEqual(got, want) {
+ t.Errorf("Got n.contents() = %v, want = %v", got, want)
+ }
+}
diff --git a/pkg/sentry/fsimpl/proc/proc.go b/pkg/sentry/fsimpl/proc/proc.go
new file mode 100644
index 000000000..31dec36de
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/proc.go
@@ -0,0 +1,16 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package proc implements a partial in-memory file system for procfs.
+package proc
diff --git a/pkg/sentry/fsimpl/proc/stat.go b/pkg/sentry/fsimpl/proc/stat.go
new file mode 100644
index 000000000..720db3828
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/stat.go
@@ -0,0 +1,127 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+import (
+ "bytes"
+ "fmt"
+
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/sentry/context"
+ "gvisor.dev/gvisor/pkg/sentry/kernel"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+)
+
+// cpuStats contains the breakdown of CPU time for /proc/stat.
+type cpuStats struct {
+ // user is time spent in userspace tasks with non-positive niceness.
+ user uint64
+
+ // nice is time spent in userspace tasks with positive niceness.
+ nice uint64
+
+ // system is time spent in non-interrupt kernel context.
+ system uint64
+
+ // idle is time spent idle.
+ idle uint64
+
+ // ioWait is time spent waiting for IO.
+ ioWait uint64
+
+ // irq is time spent in interrupt context.
+ irq uint64
+
+ // softirq is time spent in software interrupt context.
+ softirq uint64
+
+ // steal is involuntary wait time.
+ steal uint64
+
+ // guest is time spent in guests with non-positive niceness.
+ guest uint64
+
+ // guestNice is time spent in guests with positive niceness.
+ guestNice uint64
+}
+
+// String implements fmt.Stringer.
+func (c cpuStats) String() string {
+ return fmt.Sprintf("%d %d %d %d %d %d %d %d %d %d", c.user, c.nice, c.system, c.idle, c.ioWait, c.irq, c.softirq, c.steal, c.guest, c.guestNice)
+}
+
+// statData implements vfs.DynamicBytesSource for /proc/stat.
+//
+// +stateify savable
+type statData struct {
+ // k is the owning Kernel.
+ k *kernel.Kernel
+}
+
+var _ vfs.DynamicBytesSource = (*statData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (s *statData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ // TODO(b/37226836): We currently export only zero CPU stats. We could
+ // at least provide some aggregate stats.
+ var cpu cpuStats
+ fmt.Fprintf(buf, "cpu %s\n", cpu)
+
+ for c, max := uint(0), s.k.ApplicationCores(); c < max; c++ {
+ fmt.Fprintf(buf, "cpu%d %s\n", c, cpu)
+ }
+
+ // The total number of interrupts is dependent on the CPUs and PCI
+ // devices on the system. See arch_probe_nr_irqs.
+ //
+ // Since we don't report real interrupt stats, just choose an arbitrary
+ // value from a representative VM.
+ const numInterrupts = 256
+
+ // The Kernel doesn't handle real interrupts, so report all zeroes.
+ // TODO(b/37226836): We could count page faults as #PF.
+ fmt.Fprintf(buf, "intr 0") // total
+ for i := 0; i < numInterrupts; i++ {
+ fmt.Fprintf(buf, " 0")
+ }
+ fmt.Fprintf(buf, "\n")
+
+ // Total number of context switches.
+ // TODO(b/37226836): Count this.
+ fmt.Fprintf(buf, "ctxt 0\n")
+
+ // CLOCK_REALTIME timestamp from boot, in seconds.
+ fmt.Fprintf(buf, "btime %d\n", s.k.Timekeeper().BootTime().Seconds())
+
+ // Total number of clones.
+ // TODO(b/37226836): Count this.
+ fmt.Fprintf(buf, "processes 0\n")
+
+ // Number of runnable tasks.
+ // TODO(b/37226836): Count this.
+ fmt.Fprintf(buf, "procs_running 0\n")
+
+ // Number of tasks waiting on IO.
+ // TODO(b/37226836): Count this.
+ fmt.Fprintf(buf, "procs_blocked 0\n")
+
+ // Number of each softirq handled.
+ fmt.Fprintf(buf, "softirq 0") // total
+ for i := 0; i < linux.NumSoftIRQ; i++ {
+ fmt.Fprintf(buf, " 0")
+ }
+ fmt.Fprintf(buf, "\n")
+ return nil
+}
diff --git a/pkg/sentry/fsimpl/proc/sys.go b/pkg/sentry/fsimpl/proc/sys.go
new file mode 100644
index 000000000..b88256e12
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/sys.go
@@ -0,0 +1,51 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+import (
+ "bytes"
+ "fmt"
+
+ "gvisor.dev/gvisor/pkg/sentry/context"
+ "gvisor.dev/gvisor/pkg/sentry/kernel"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+)
+
+// mmapMinAddrData implements vfs.DynamicBytesSource for
+// /proc/sys/vm/mmap_min_addr.
+//
+// +stateify savable
+type mmapMinAddrData struct {
+ k *kernel.Kernel
+}
+
+var _ vfs.DynamicBytesSource = (*mmapMinAddrData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (d *mmapMinAddrData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ fmt.Fprintf(buf, "%d\n", d.k.Platform.MinUserAddress())
+ return nil
+}
+
+// +stateify savable
+type overcommitMemory struct{}
+
+var _ vfs.DynamicBytesSource = (*overcommitMemory)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (d *overcommitMemory) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ fmt.Fprintf(buf, "0\n")
+ return nil
+}
diff --git a/pkg/sentry/fsimpl/proc/task.go b/pkg/sentry/fsimpl/proc/task.go
new file mode 100644
index 000000000..c46e05c3a
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/task.go
@@ -0,0 +1,261 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+import (
+ "bytes"
+ "fmt"
+
+ "gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/sentry/context"
+ "gvisor.dev/gvisor/pkg/sentry/kernel"
+ "gvisor.dev/gvisor/pkg/sentry/limits"
+ "gvisor.dev/gvisor/pkg/sentry/mm"
+ "gvisor.dev/gvisor/pkg/sentry/usage"
+ "gvisor.dev/gvisor/pkg/sentry/usermem"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+)
+
+// mapsCommon is embedded by mapsData and smapsData.
+type mapsCommon struct {
+ t *kernel.Task
+}
+
+// mm gets the kernel task's MemoryManager. No additional reference is taken on
+// mm here. This is safe because MemoryManager.destroy is required to leave the
+// MemoryManager in a state where it's still usable as a DynamicBytesSource.
+func (md *mapsCommon) mm() *mm.MemoryManager {
+ var tmm *mm.MemoryManager
+ md.t.WithMuLocked(func(t *kernel.Task) {
+ if mm := t.MemoryManager(); mm != nil {
+ tmm = mm
+ }
+ })
+ return tmm
+}
+
+// mapsData implements vfs.DynamicBytesSource for /proc/[pid]/maps.
+//
+// +stateify savable
+type mapsData struct {
+ mapsCommon
+}
+
+var _ vfs.DynamicBytesSource = (*mapsData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (md *mapsData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ if mm := md.mm(); mm != nil {
+ mm.ReadMapsDataInto(ctx, buf)
+ }
+ return nil
+}
+
+// smapsData implements vfs.DynamicBytesSource for /proc/[pid]/smaps.
+//
+// +stateify savable
+type smapsData struct {
+ mapsCommon
+}
+
+var _ vfs.DynamicBytesSource = (*smapsData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (sd *smapsData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ if mm := sd.mm(); mm != nil {
+ mm.ReadSmapsDataInto(ctx, buf)
+ }
+ return nil
+}
+
+// +stateify savable
+type taskStatData struct {
+ t *kernel.Task
+
+ // If tgstats is true, accumulate fault stats (not implemented) and CPU
+ // time across all tasks in t's thread group.
+ tgstats bool
+
+ // pidns is the PID namespace associated with the proc filesystem that
+ // includes the file using this statData.
+ pidns *kernel.PIDNamespace
+}
+
+var _ vfs.DynamicBytesSource = (*taskStatData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (s *taskStatData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ fmt.Fprintf(buf, "%d ", s.pidns.IDOfTask(s.t))
+ fmt.Fprintf(buf, "(%s) ", s.t.Name())
+ fmt.Fprintf(buf, "%c ", s.t.StateStatus()[0])
+ ppid := kernel.ThreadID(0)
+ if parent := s.t.Parent(); parent != nil {
+ ppid = s.pidns.IDOfThreadGroup(parent.ThreadGroup())
+ }
+ fmt.Fprintf(buf, "%d ", ppid)
+ fmt.Fprintf(buf, "%d ", s.pidns.IDOfProcessGroup(s.t.ThreadGroup().ProcessGroup()))
+ fmt.Fprintf(buf, "%d ", s.pidns.IDOfSession(s.t.ThreadGroup().Session()))
+ fmt.Fprintf(buf, "0 0 " /* tty_nr tpgid */)
+ fmt.Fprintf(buf, "0 " /* flags */)
+ fmt.Fprintf(buf, "0 0 0 0 " /* minflt cminflt majflt cmajflt */)
+ var cputime usage.CPUStats
+ if s.tgstats {
+ cputime = s.t.ThreadGroup().CPUStats()
+ } else {
+ cputime = s.t.CPUStats()
+ }
+ fmt.Fprintf(buf, "%d %d ", linux.ClockTFromDuration(cputime.UserTime), linux.ClockTFromDuration(cputime.SysTime))
+ cputime = s.t.ThreadGroup().JoinedChildCPUStats()
+ fmt.Fprintf(buf, "%d %d ", linux.ClockTFromDuration(cputime.UserTime), linux.ClockTFromDuration(cputime.SysTime))
+ fmt.Fprintf(buf, "%d %d ", s.t.Priority(), s.t.Niceness())
+ fmt.Fprintf(buf, "%d ", s.t.ThreadGroup().Count())
+
+ // itrealvalue. Since kernel 2.6.17, this field is no longer
+ // maintained, and is hard coded as 0.
+ fmt.Fprintf(buf, "0 ")
+
+ // Start time is relative to boot time, expressed in clock ticks.
+ fmt.Fprintf(buf, "%d ", linux.ClockTFromDuration(s.t.StartTime().Sub(s.t.Kernel().Timekeeper().BootTime())))
+
+ var vss, rss uint64
+ s.t.WithMuLocked(func(t *kernel.Task) {
+ if mm := t.MemoryManager(); mm != nil {
+ vss = mm.VirtualMemorySize()
+ rss = mm.ResidentSetSize()
+ }
+ })
+ fmt.Fprintf(buf, "%d %d ", vss, rss/usermem.PageSize)
+
+ // rsslim.
+ fmt.Fprintf(buf, "%d ", s.t.ThreadGroup().Limits().Get(limits.Rss).Cur)
+
+ fmt.Fprintf(buf, "0 0 0 0 0 " /* startcode endcode startstack kstkesp kstkeip */)
+ fmt.Fprintf(buf, "0 0 0 0 0 " /* signal blocked sigignore sigcatch wchan */)
+ fmt.Fprintf(buf, "0 0 " /* nswap cnswap */)
+ terminationSignal := linux.Signal(0)
+ if s.t == s.t.ThreadGroup().Leader() {
+ terminationSignal = s.t.ThreadGroup().TerminationSignal()
+ }
+ fmt.Fprintf(buf, "%d ", terminationSignal)
+ fmt.Fprintf(buf, "0 0 0 " /* processor rt_priority policy */)
+ fmt.Fprintf(buf, "0 0 0 " /* delayacct_blkio_ticks guest_time cguest_time */)
+ fmt.Fprintf(buf, "0 0 0 0 0 0 0 " /* start_data end_data start_brk arg_start arg_end env_start env_end */)
+ fmt.Fprintf(buf, "0\n" /* exit_code */)
+
+ return nil
+}
+
+// statmData implements vfs.DynamicBytesSource for /proc/[pid]/statm.
+//
+// +stateify savable
+type statmData struct {
+ t *kernel.Task
+}
+
+var _ vfs.DynamicBytesSource = (*statmData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (s *statmData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ var vss, rss uint64
+ s.t.WithMuLocked(func(t *kernel.Task) {
+ if mm := t.MemoryManager(); mm != nil {
+ vss = mm.VirtualMemorySize()
+ rss = mm.ResidentSetSize()
+ }
+ })
+
+ fmt.Fprintf(buf, "%d %d 0 0 0 0 0\n", vss/usermem.PageSize, rss/usermem.PageSize)
+ return nil
+}
+
+// statusData implements vfs.DynamicBytesSource for /proc/[pid]/status.
+//
+// +stateify savable
+type statusData struct {
+ t *kernel.Task
+ pidns *kernel.PIDNamespace
+}
+
+var _ vfs.DynamicBytesSource = (*statusData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (s *statusData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ fmt.Fprintf(buf, "Name:\t%s\n", s.t.Name())
+ fmt.Fprintf(buf, "State:\t%s\n", s.t.StateStatus())
+ fmt.Fprintf(buf, "Tgid:\t%d\n", s.pidns.IDOfThreadGroup(s.t.ThreadGroup()))
+ fmt.Fprintf(buf, "Pid:\t%d\n", s.pidns.IDOfTask(s.t))
+ ppid := kernel.ThreadID(0)
+ if parent := s.t.Parent(); parent != nil {
+ ppid = s.pidns.IDOfThreadGroup(parent.ThreadGroup())
+ }
+ fmt.Fprintf(buf, "PPid:\t%d\n", ppid)
+ tpid := kernel.ThreadID(0)
+ if tracer := s.t.Tracer(); tracer != nil {
+ tpid = s.pidns.IDOfTask(tracer)
+ }
+ fmt.Fprintf(buf, "TracerPid:\t%d\n", tpid)
+ var fds int
+ var vss, rss, data uint64
+ s.t.WithMuLocked(func(t *kernel.Task) {
+ if fdTable := t.FDTable(); fdTable != nil {
+ fds = fdTable.Size()
+ }
+ if mm := t.MemoryManager(); mm != nil {
+ vss = mm.VirtualMemorySize()
+ rss = mm.ResidentSetSize()
+ data = mm.VirtualDataSize()
+ }
+ })
+ fmt.Fprintf(buf, "FDSize:\t%d\n", fds)
+ fmt.Fprintf(buf, "VmSize:\t%d kB\n", vss>>10)
+ fmt.Fprintf(buf, "VmRSS:\t%d kB\n", rss>>10)
+ fmt.Fprintf(buf, "VmData:\t%d kB\n", data>>10)
+ fmt.Fprintf(buf, "Threads:\t%d\n", s.t.ThreadGroup().Count())
+ creds := s.t.Credentials()
+ fmt.Fprintf(buf, "CapInh:\t%016x\n", creds.InheritableCaps)
+ fmt.Fprintf(buf, "CapPrm:\t%016x\n", creds.PermittedCaps)
+ fmt.Fprintf(buf, "CapEff:\t%016x\n", creds.EffectiveCaps)
+ fmt.Fprintf(buf, "CapBnd:\t%016x\n", creds.BoundingCaps)
+ fmt.Fprintf(buf, "Seccomp:\t%d\n", s.t.SeccompMode())
+ return nil
+}
+
+// ioUsage is the /proc/<pid>/io and /proc/<pid>/task/<tid>/io data provider.
+type ioUsage interface {
+ // IOUsage returns the io usage data.
+ IOUsage() *usage.IO
+}
+
+// +stateify savable
+type ioData struct {
+ ioUsage
+}
+
+var _ vfs.DynamicBytesSource = (*ioData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (i *ioData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ io := usage.IO{}
+ io.Accumulate(i.IOUsage())
+
+ fmt.Fprintf(buf, "char: %d\n", io.CharsRead)
+ fmt.Fprintf(buf, "wchar: %d\n", io.CharsWritten)
+ fmt.Fprintf(buf, "syscr: %d\n", io.ReadSyscalls)
+ fmt.Fprintf(buf, "syscw: %d\n", io.WriteSyscalls)
+ fmt.Fprintf(buf, "read_bytes: %d\n", io.BytesRead)
+ fmt.Fprintf(buf, "write_bytes: %d\n", io.BytesWritten)
+ fmt.Fprintf(buf, "cancelled_write_bytes: %d\n", io.BytesWriteCancelled)
+ return nil
+}
diff --git a/pkg/sentry/fsimpl/proc/version.go b/pkg/sentry/fsimpl/proc/version.go
new file mode 100644
index 000000000..e1643d4e0
--- /dev/null
+++ b/pkg/sentry/fsimpl/proc/version.go
@@ -0,0 +1,68 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package proc
+
+import (
+ "bytes"
+ "fmt"
+
+ "gvisor.dev/gvisor/pkg/sentry/context"
+ "gvisor.dev/gvisor/pkg/sentry/kernel"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
+)
+
+// versionData implements vfs.DynamicBytesSource for /proc/version.
+//
+// +stateify savable
+type versionData struct {
+ // k is the owning Kernel.
+ k *kernel.Kernel
+}
+
+var _ vfs.DynamicBytesSource = (*versionData)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (v *versionData) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ init := v.k.GlobalInit()
+ if init == nil {
+ // Attempted to read before the init Task is created. This can
+ // only occur during startup, which should never need to read
+ // this file.
+ panic("Attempted to read version before initial Task is available")
+ }
+
+ // /proc/version takes the form:
+ //
+ // "SYSNAME version RELEASE (COMPILE_USER@COMPILE_HOST)
+ // (COMPILER_VERSION) VERSION"
+ //
+ // where:
+ // - SYSNAME, RELEASE, and VERSION are the same as returned by
+ // sys_utsname
+ // - COMPILE_USER is the user that build the kernel
+ // - COMPILE_HOST is the hostname of the machine on which the kernel
+ // was built
+ // - COMPILER_VERSION is the version reported by the building compiler
+ //
+ // Since we don't really want to expose build information to
+ // applications, those fields are omitted.
+ //
+ // FIXME(mpratt): Using Version from the init task SyscallTable
+ // disregards the different version a task may have (e.g., in a uts
+ // namespace).
+ ver := init.Leader().SyscallTable().Version
+ fmt.Fprintf(buf, "%s version %s %s\n", ver.Sysname, ver.Release, ver.Version)
+ return nil
+}